Ripple remover



y 4, 1957 I R. M. PEEBLES 2,792,049

RIFPLE REMOVER Filed July 21, 1952 3 Sheets-Sheet l INVENTOR. E0)" M.PEEBLEG @gbx.

ATTOENEY May 14, 1957 R. M. PEEBLES RIPPLE REIMOVER 3 Sheets-Sheet 2Filed July 21, 1952 E &

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5 P0) M. PEEBLES ATTOENEY United States Patent RIPPLE REMOVER Roy M.Peebles, Atlanta, Ga.

Application July 21, 1952, Serial No. 299,998

6 Claims. (Cl. 153-54) This invention relates to a means and method ofremoving ripples from strips of sheet material and more particularly toa means and method of removing ripples from slit stock material commonlyused in forming Venetian blind slats.

in manufacturing Venetian blind slats from rectangular sheets of steelor aluminum, the metal is first slit into long thin strips approximatelytwo inches wide and these strips are rolled upon reels thereafter. Thereels are next transported to an oven where the slat material isunreeled and passed between paint applying rollers, then through abaking oven and rewound upon a reel. The reel is next transported to aslat forming machine where the slat material is formed in itsconventional curvilinear shape and cut in proper lengths, with aperturesbeing formed adjacent the ends thereof to receive the customarysupporting cords.

in order for the finished slat to be usable in a first grade Venetianblind, it is necessary that the edges of this slat be straight andparallel. Because of the stresses in the thin narrow Venetian blindstock resulting from the treatment of this stock prior to the time thatit is received by the slat forming machine, many of the Venetian blindslats have edges which are rippled or wavy or uneven in length. If thefinished slat has edges which are uneven in length, the slat is twistedlongitudinally so that it is entirely unusable. Generally, it has beenfound that entire reels of the wavy or rippled Venetian blind stock mustbe rejected as scrap material, unless this material can be stretched orso treated that the ripples or waves are removed.

Many attempts have been made to utilize rippled Venetian blind stock,but none of the prior art methods have proven entirely satisfactorysince no process, heretofore, has been more than about 50% effective inproducing a satisfactory straight Venetian blind slat from rippled stockmaterial. One method, very generally used in the art to remove ripplesfrom Venetian blind slats, is to so arrange the rollers of a slatforming machine that a sway or slight longitudinal curve is placed inthe slat, thus, in effect, making the edges of the concave slat slightlylonger than the center. Slats formed in this manner are inferior; and,if incorporated with straight Venetian blind slats, the curved slat willbe readily noticed.

Another method of removing ripples from Venetian blind slats is known inthe art as center stretching and employs a complicated and expensivemachine having a series of rollers through which the slat material ispassed. In this center stretching method, an attempt is made to pull orlongitudinally stretch the center of the slat material so that thecenter and the edges of this material are substantially the same length;however, a great deal of care must be exercised to effect the precisestretching desired. With too much stretching, the slat material readilyparts or shears; and, even with the maximum amount of stretching, thecenter stretching method is only approximately 50% effective.

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Both methods mentioned above are time consuming and require theattention of a skilled operator who must make finite adjustments in themachinery in order to produce a slat which may or may not be usable. Theindustry has long searched for a convenient method of producing astraight finished slat from rippled stock material so that rejectedreels of rippled slat material may be utilized to produce a straightslat having ripple-free edges.

Accordingly, it is an object of my invention to provide an improvedmeans and method of producing a straight ripple-free Venetian blind slatfrom rippled stock material.

Another object of my invention is to provide a means and method ofproducing Venetian blind slats from rippled stock material which willprovide substantially usable slats.

Another object of my invention is to provide a machine whioh willautomatically remove ripples from strip material, which machine willoperate in conjunction with a conventional slat forming machine.

Another object of my invention is to provide an inexpensive, durable andeffective -ripple-removing machine, having few moving parts and which iscapable of being operated by an inexperienced operator in conjunctionwith a slat forming machine.

Another object of my invention is to provide a process wherein the edgesof strip metal material are bent beyond their elastic limits in. such away as to realign the edges thereof.

Another object of my invention is to provide a machine for removingripples from stock material in the manufacture of Venetian blind slats,which machine Will automatically detect the presence of ripples alongthe edges of the slat and thereafter automatically adjust itself toremove these ripples.

Other and further objects and advantages of my invention will becomeapparent from the following description when taken in conjunction withthe accompanying drawings in which like characters of referencedesignate corresponding parts throughout the several views, and wherein:

Fig. l is a top plan view of a conventional slat forming machine, havingmy ripple removing machine incorporated therewith.

Fig. 1-A is a cross-sectional view of the conventional preformingrollers.

Fig. 1-B is a cross-sectional view of the conventional forming rollers.

Fig. 2 is a front view of a machine constructed in accordance with myinvention.

Fig. 3 is .a bottom view of the machine illustrated in Fig. 2.

Fig. 4 is a view of a detail.

Fig. 5 is a top view of a detail illustrating an optional arrangement ofthe pulley driving the machine illustrated in Fig. 2.

Fig. 6 is a partially broken side View of the pulley illustrated in Fig.5.

Fig. 7 is an electrical wiring diagram illustrating the automatic rippledetector device which may be incorporated with the machine illustratedin Fig. 1.

Fig. 8 is a cross-sectional view of the Venetian blind stock materialbefore it enters my machine.

Fig. 9 is a cross-sectional view of the Venetian blind stock materialafter it has passed through the machine illustrated in Fig. 2.

Fig. 10 is a cross-sectional view of the Venetian blind stock materialafter it has passed through the forming rollers of the machineillustrated in Fig. 1.

Fig. 11 is a cross-sectional view of the Venetian blind stock materialafter it has passed through the machine illustrated in Fig. 4.

3 Fig. 12 is a cross-sectional view taken along line 12--12 in Fig. 1.

Fig. 13 is a cross-sectional view taken along line 13-13 in Fig. 1.

Fig. 14 is a crosssectio1al view taken along line 14-14 in Fig. 1.

Referring now to the embodiment chosen for purpose of illustration, inFig. 1 is shown a Venetian blind slat forming machine including a base12, alignment roller 13, pre-forming rollers 14, pie-forming roller arm14, forming rollers 15, 15, guide rollers 16, idler 17, limit switch 18,feed rollers 19, aperture punches 26, cutter 21, and micro-switch 22,all arranged in conventional manner, said forming rollers 15, 15' beinggenerally of the type illustrated in U. S. Patents No. 2.262- 550 andNo. 2,370,215.

Mounted on arm 14 and spaced between alignment roller 13 and pre-formingrollers 14 is my ripple removing machine which is denoted by numeral 23in Fig. 1 and which is also shown in detail in Figs. 2 and 3. Slat stockmaterial 24 is fed from reel 25 on base 12, around alingnment roller 13and through my ripple removing machine 23; then the stock material 24 isfed through the remaining parts of the machine as shown in Fig. l.Forming rollers 15, 15 are driven by motor (not shown) which iscontrolled by limit switch 18, and a separate motor (not shown) drivesfeed rollers 19, all as is well understood in the art. A continuous belt25 extends around pulley 26' on forming roller 15 and to machine 23 toprovide power therefor.

In Figs. 2 and 3, my ripple removing machine 23 is shown as comprising asubstantially rectangular frame having upper arm 27 and lower arm 28,spaced from each other by an end joining side 29 and a gear supportingside 30. Aligned axle pins 31, 31' pass respectively through arms 27 and28, adjacent end joining side 29 and support for rotation, female roller32 therebetween. The female roller 32 is a solid symmetrical cylindricalroller whose ends and center section are substantially the samediameter, with the center section comprising substantially one-third ofthe length of the roller. Between the center section and either endthereof, roller 32 is machined to a smaller uniform diameter, withconcaved fillets between the ends and this smaller section andconcaveconvex sections between the center portion and the smallersections.

A male roller 33, which is knobbed on either end thereof tosubstantially correspond with the small diameter sections of the femaleroller 32, is mounted adjacent this female roller and is fixed to shaft34 which is journaled in aligned apertures in arms 35, 35 of yoke 36.Yoke 36 is slidably retained by apertures 37 in upper and lower arms 27and 28. Male roller 33 has a convexed periphery, adjacent each endthereof to correspond with the concaved fillet sections adjacent eitherend of the female roller 32, the major diameter of the male roller 33being substantially the sarne as the major diameter of the female roller32. Male roller 33 is so formed that when in contact with female roller32 only the periphery adjacent the end portions are contiguous withfemale roller 32, with the diameter of the knobbed sections taperingslightly toward the center; thus when stock material 24 is passedbetween rollers 32 and 33, with these rollers exerting pressure thereon,only the edges of this stock material will be firmly held by theserollers and the material bent, as indicated in Fig. 9. It is veryimportant since only the edges are to be held tightly and that centersection of male roller 33 be of sutliciently small diameter that thereis substantial clearance between the center section of female roller 32and the center section of male roller 33, so that the center section ofroller 33 will not touch the metal stock material as it is acted on bymy machine.

In Fig. 4, is illustrated a second species of my invention whichconsists in substituting for female roller 32, in Fig. 2, female roller32' in Fig. 4. Female roller 32 is a solid cylindrical roller ofsubstantially the same diameter as the small diameter of female roller32 and having belled or fillet sections forming the end portionsthereof, which are identical with the ends or fillet sections of femaleroller 32.

Any convenient means for adjusting the distance between the rippleremoving rollers, male roller 33 and female roller 32 or female roller32 may be incorporated with my invention. In Figs. 2 and 4, for example,I have provided a pressure adjusting screw 38 which threadably engagesyoke 36 and is fixed to bevel gear 39, supported in an appropriateaperture within gear supporting side 30. A second bevel gear 39' engagesbevel gear 39 and extends through upper arm 27, being provided with anexternal knurled operator knob 40. A pulley 41 is fixed to shaft 34 andwhen my ripple removing machine 23 is mounted on the slat formingmachine, as illustrated in Fig. 1, this pulley is driven by belt 26. Itwill be remembered that rollers 15, 15' are driven by a motor (notshown) which is controlled by limit switch 18. Therefore, since belt 26is driven from pulley 26', and pulley 26 is affixed to roller 15, thetravel of belt 26 and hence the rotation of pulley 41 is controlled bylimit switch 18.

According to my invention, when the ripple removing machine 23 ismounted on the slat forming machine, as illustrated in Fig. 1, the slatforming machine may normally be operated with good stock material bypassing the stock material through the ripple removing machine 23, butapplying no pressure thereto. If ripples are detected in the finishedVenetian blind slat, the operator need only rotate the operator knob 40to thereby move male roller 33 into close proximity with female roller32, thus applying pressure to the slat stock material 24 passingtherebetween. Before the slat stock material 24 enters machine 23, ithas a cross-section as illustrated in Fig. 8; however, with pressureapplied to this material by rollers 32 and 33, the cross-section ischanged to that illustrated in Fig. 9. In Fig. 9, the slat stockmaterial has sharp bends adjacent each edge thereof and other sharpbends substantially one-third of the distance in from either edgethereof. Of course, if female roller 32 is substituted for female roller32, sharp bends will only appear adjacent each edge thereof, as shown inFig. 11.

From my ripple removing machine 23, the slat stock material next entersthe pro-forming rollers 14 and the forming rollers 15, 15 where thecenter of the stock material is curved, as illustrated in Fig. 10. It isto be remembered that my machine should be arranged so that the convexedroller of the pre-forming rollers 14 and forming rollers 15, 15 will actagainst the same side of the slat stock material that was previouslyacted against by the male roller 33, thus causing the center section ofthe slat stock material 24 to be concaved first in one direction andthen in the other.

Generally, I have found that stresses in the Venetian blind stockmaterial, which result in rippled or twisted finished slats, manifestthemselves in the stock material as waves of long wave length and lowamplitude and generally result in a stock material having edges whichare uneven in length; therefore minute and proper adjustmentslongitudinally of the stock material will eliminate these waves orripples causing sharp bends immediately adjacent these edges, andtransversely thereof, will induce realignment of the metal adjacentthese bends sufliciently to re-align the structure of the slat stockmaterial to such an extent that the ripples or waves are removedtherefrom.

According to my invention, it is desirable for belt 26 to drive pulley41, and hence male roller 33, at such a velocity that the slat stockmaterial 24 is driven through my machine 23 at substantially the samespeed as it is pulled through the forming rollers 15, 15; therefore,there is only sufficient tension placed on the stock material betweenthe ripple removing machine 23 and the forming rollers 15, 15' to holdthe slat stock material 24 in alignment.

Referring now to Figs. 5, 6 and 7, I have provided an automatic controlwhich will regulate the amount of pressure applied on the slat stockmaterial 24 by rollers 32 and 33. In Fig. 7, I have arranged a lightsource 42 which shines on the bottom or ccncaved side of the Venetianblind stock material 24. This light source 42 may be located at anyconvenient place along the travel of the Venetian blind stock materialafter it has passed between the forming rollers 15, 15'. Electric eyes43, 43 are located adjacent the edges of slat stock material 24 so thatit may detect the light shining on the opposite edge only when a rippleappears on the edge adjacent the electric eye. When light falls oneither electric eye 43 or 43, a circuit is completed which will energizesolenoids 44 and 45, thus closing switches 46 and 47, respectively. Withswitch 46 closed, current will be passed to reversible motor 48 drivingadjusting screw 38 in a direction to move male roller 33 toward femaleroller 32.

As pressure is applied to stock material 24 by rollers 32 and 33, it isobvious that more power will be required to drive roller 33. I havetherefore substituted for pulley 26 a pulley 49 illustrated in Figs. and6 which is journaled on shaft 49' of forming roller and resiliently heldto roller 15 by spring 50 as illustrated in Fig. 6. Normally, thetension in spring 50 is sulficient to allow pulley 49 to drive belt 26without appreciable relative angular displacement of pulley 49 withrespect to forming roller 15'. slot 52 on pulley 49. An electricalcontact 53, positioned appropriately in slot 52, is connected to slipring 54 on pulley 49; and, with suflicient angular displacement of shaft49' with respect to pulley 49, pin 51 will be rotated to engage contact53. Pin 51 is electrically connected to slip ring 55 on shaft 49', andslip rings 54 and 55 are provided with appropriate brushes 56, 56',respectively, which lead therefrom. In Fig. 7, it will be seen that whenthe circuit between brushes 56, 56' is closed, power is supplied toreverse motor 48, thereby moving roller 33 away from roller 32. Inaddition, current is passed through solenoid 57 and solenoid 58, therebyopening switch 46 and closing switch 59. Switch 46 is a normally openswitch and therefore, unless ripples are detected by electric eyes 43,43', no current will be passed to tighten roller 33; however, if bothcircuits energizing solenoids 45 and 58 are simultaneously closed, oneby the detection of ripples in the slat stock material 24 and the otherby an indication of an overload on pulley 49, both switches 47 and 59will be closed to energize alarm 60 to indicate to the operator that themachine is not functioning properly. Thus it may be seen that after ashort section of slat material has passed through rollers 32 and 33, theautomatic control is sufliciently adjusted that substantially no otherripple should appear. Of course, since the electric eyes 43, 43' arelocated in the path of the slat, after it has been formed, the rippleswhich are detected by the electric eyes cannot be removed in theoperation, but since the ripples generally follow a pattern throughoutthe reel of stock material, substantially the entire reel thereafterwill be ripple free.

It will be obvious to those skilled in the art that many variations maybe made in the embodiment chosen for the purpose of illustration withoutdeparting from the scope of my invention as defined in the appendedclaims.

I claim:

1. In a machine for removing ripples from strip material, opposed maleand female rollers, said male rollers being provided with knobbed endsections and a center section of substantially smaller diameter thansaid end sections thereof, said female roller having a center section ofsubstantially the same length as the center section of the said maleroller and having flaring ends thereof of A pin 51 is fixed to shaft 49'and rides in a substantially the same diameter as its said centersection, said female roller being provided with intermediate sectionsbetween said ends thereof and said center section thereof and of smallerdiameter than said center sections and end sections thereof, therelative dimensions of roller sections named being such that when therollers are in closed operative position the knobbed end sections of themale roller enter into the grooves formed by the intermediate sections,flaring end sections, and center section of said female roller, and actin cooperation with the female roller to grip the edge portionsoutwardly of the center portion of the strip material and further suchthat a clearance exists between the center section of the male rollerand the center portion of the strip material when the edge portions ofthe strip are gripped as aforesaid.

2. The structure defined in claim 1 wherein said flaring ends arecurved, said knobbed ends of said male roller have convexed extremeperipheries substantially corresponding to and adapted to register withthe curvature of said flaring ends of said female roller, said knobbedends also having flat peripheral portions merging with said convexedperipheries and each tapering toward said center section of said maleroller.

3. The structure defined in claim 1 including a frame supporting forrotation said rollers, and means connected to said frame for moving oneof said rollers toward the other of said rollers to apply pressure tosaid strip material therebetween.

4. The structure defined in claim 1 including a frame, axle meanscarried by said frame on which one of said rollers is rotatable, a yokecarrying for rotation the other of said rollers, said yoke being movablein said frame, means for moving said yoke, and power means for drivingone of said rollers.

5. The process of forming curved Venetian blind slat strip material fromsubstantially flat strip material com prising the steps of gripping andholding only the edge portions of the strip material and bending thesame to form a groove adjacent each of its edges and an intermediategroove which faces in the opposite direction, and thereafterprogressively bending said slat material into a smooth curvedcross-sectional shape.

6. The process of forming curved Venetian blind slat strip material fromsubstantially flat strip material comprising the steps of progressivelygripping and holding the edge portions of said strip material to formgrooves adjacent each of its edges and an intermediate groove whichfaces in the opposite direction, said grooves adjacent the ends havingfiat surfaces in substantially the same plane and said intermediategroove having a flat surface in a plane substantially parallel to theaforesaid plane, and thereafter progressively bending said slat materialin a direction such that said intermediate groove is deformed in thedirection of said grooves adjacent the ends to form said slat materialinto a smooth curved cross-sectional s ape.

References Cited in the file of this patent UNITED STATES PATENTS471,407 Westaway Mar. 22, 1892 1,125,984 Dumas Jan. 26, 1915 1,649,613Olson Nov. 15, 1927 1,929,771 Burns Oct. 10, 1933 2,176,115 Yoder Oct.17, 1939 2,183,969 McKinney Dec. 19, 1939 2,333,282 Wilson Nov. 2, 19432,471,490 Mercer May 31, 1949 2,562,447 Colburn July 31, 1951 2,717,625Johnson Sept. 13, 1955 2,717,626 Sherwood Sept. 13, 1955 FOREIGN PATENTS264,534 Great Britain June 30, 1927

